Amentotaxus argotaenia (Hance) Pilg. is a threatened conifer with a wide distribution range from North to Central Vietnam due to habitat loss and over-exploitation. To provide information for its conservation and sustainable management, in the present study, genetic diversity and population genetic structure for 200 trees from eight populations, representing the natural distribution range of this species were estimated using nuclear microsatellites. The results showed a moderate genetic diversity of A. argotaenia (HO = 0.331, HE = 0.358). Significant heterozygosity deficits were detected in three populations in the Northeast area. Genetic differentiation was low in the same distribution area and high in different areas. However, the gene flow among the studied populations was relatively high (Nm = 1.17). Habitat fragmentation, geographical distance and high mountain range can be the major factors that reduce gene exchange between different areas. Various clustering analyses distinguished three major genetic groups related to the three distribution areas of this species in Vietnam. Based on the study results, we propose that some populations could be prioritized for in situ conservation due to their high genetic diversity with high allelic richness or private alleles, meanwhile other populations should be collected for ex situ conservation as genetic resources in the future.

Various Lycopodium alkaloids have been studied for their various biological activities including anti-inflammatory, antioxidant, immunomodulatory, and neuroprotective activities. Moreover, these alkaloid compounds have high potential in the treatment of neuron degenerative disease. This study has been carried out to test the effect of Huperzia serrata (Thunb.) Trevis, and Lycopodium clavatum L alkaloid fractions on the mouse neural stem cells (NSCs). Firstly, the alkaloid fractions were used to verify its toxicity on NSCs. The multiple concentrations of alkaloid fractions from H. serrata (0.044; 0.088; 0.175; 0.35; 0.7; 1.4 mg/ml) and L. clavatum (0.031; 0.063; 0.125; 0.25; 0.50; 1.0; 2.0 mg/ml) have been used for the treatment of NSCs at period of 48h incubation. Results of the study suggested that the IC50 value of H. serrata and L. clavatum was 0.56 mg/ml and 0.50 mg/ml, respectively. Then, the NSCs were differentiated in the presence of 5 and 10 µg/ml of alkaloid fraction from H. serrata; 0.625 and 1.25 µg/ml of alkaloid fraction from L. clavatum for 6 days. Here, we observed the primary NSCs treated with alkaloid fraction extract from H. serrata showed the increased gene expression level of early neuron TUBB3 and neuron-specific cytoskeleton MAP2. On the other hand, the L. clavatum alkaloid fraction increased the expression of neural stem cell marker genes (Nestin and PAX6) and decreased neuron marker genes. In conclusion, these results established that alkaloid fraction from H. serrata promoted differentiation of the mouse NSCs to neuron cells, and L. clavatum extract had a capacity for stemness maintenance.

Transcatheter aortic valve replacement (TAVR) through the carotid artery in middle-aged patients with severe aortic stenosis and chronic hemodialysis has been a challenge in clinical practice because of the complex technique. A 60-year-old man was admitted to our hospital because of his symptomatic severe aortic stenosis. With the high risk of open surgery due to chronic hemodialysis, TAVR was selected after an in-depth discussion between the heart team and the patient. The transfemoral access route was not appropriate due to severe calcifications and tortuous iliofemoral arteries, therefore, the left carotid route was chosen. A 29-mm CoreValve Evolut R system was successfully implanted without any complications. His symptoms significantly improved at 12- month follow-up, without any major cardiovascular adverse events. TAVR via the carotid artery thus demonstrates the feasibility, safety, and effectiveness in such complex conditions.